We present the results of high resolution spectroscopy of the prototype polar AM Herculis observed with Chandra High Energy Transmission Grating .
The X-ray spectrum contains hydrogen-like and helium-like lines of Fe , S , Si , Mg , Ne and O with several Fe L-shell emission lines .
The forbidden lines in the spectrum are generally weak whereas the hydrogen-like lines are stronger suggesting that emission from a multi-temperature , collisionally ionized plasma dominates .
The helium-like line flux ratios yield a plasma temperature of 2 MK and a plasma density 1–9 \times 10 ^ { 12 } cm ^ { -3 } , whereas the line flux ratio of Fe xxvi to Fe xxv gives an ionization temperature of 12.4 ^ { +1.1 } _ { -1.4 } keV .
We present the differential emission measure distribution of AM Her whose shape is consistent with the volume emission measure obtained by multi-temperature APEC model .
The multi-temperature plasma model fit to the average X-ray spectrum indicates the mass of the white dwarf to be \sim 1.15 M _ { \sun } .

From phase resolved spectroscopy , we find the line centers of Mg xii , S xvi , resonance line of Fe xxv , and Fe xxvi emission modulated by a few hundred to 1000 km s ^ { -1 } from the theoretically expected values indicating bulk motion of ionized matter in the accretion column of AM Her .
The observed velocities of Fe xxvi ions are close to the expected shock velocity for a 0.6 M _ { \sun } white dwarf .
The observed velocity modulation is consistent with that expected from a single pole accreting binary system .